TUNICA, Miss. — Marie Barnard was delighted when, after decades of silence on the topic, Mississippi passed a law requiring school districts to teach sex education. But the lesson involving the Peppermint Pattie wasn't what she had in mind for her sons.

The curricula adopted by the school district in Oxford called on students to unwrap a piece of chocolate, pass it around class and observe how dirty it became.

"They're using the Peppermint Pattie to show that a girl is no longer clean or valuable after she's had sex — that she's been used," said Barnard, who works in public health. "That shouldn't be the lesson we send kids about sex."

She and other parents lobbied the district to teach about contraception, not just abstinence. After all, as she and other parents noted, 76% of Mississippi teenagers report having sex before the end of high school.

Mississippi has one of the highest teen pregnancy rates in the country, with 50 births per 1,000 females aged 15 to 19 in 2011 — compared with 31 per 1,000 nationally. A third of all babies born in Mississippi are to teenage mothers. Access to contraceptives is low, especially in some rural areas where drug stores have been known to refuse to sell condoms to minors.

Alarmed by the high poverty and low education rates tied to teen pregnancy, the business community pushed the Legislature to pass a bill compelling districts to implement sex education by the 2012-13 school year.

But parts of the law designed to appease conservatives in this deeply religious state have stymied those who want to teach about safe sex.

"It [the state law] requires boys and girls to be taught about sex in separate classes[.]" Seriously?!? What year is it? What country are we in? Is the deep South really *that* far behind the rest of the country? Holy mackerel. Not even going into the "homosexuality is...

To participate in sex education classes, students must get a signed permission slip from their parents, which some districts that don't support the law have made especially challenging. In some classes, the only discussion about condoms focuses on their failure rates. And the law requires that students be taught that homosexual activity is technically illegal in Mississippi.

"Basically, the law stinks in Mississippi," Barnard said. "It was exciting to see the state address what is really a serious problem for the state, but they only took a little step forward."

The law expires in 2016, and sex education advocates hope they'll be able to prove by then that sex ed helps prevent teen pregnancy so they can renew or expand the law. But they have another challenge first: making sure that schools follow the law, which has no enforcement mechanism. According to a study published by the Center for Mississippi Health Policy in February, 12% of districts still aren't teaching any sex ed.

The law required school districts to choose between abstinence-only programs that tell students to wait until marriage to have sex, or "abstinence-plus" programs that urge abstinence but also teach about contraception.

Of Mississippi's 151 school districts and four special schools, 81 chose abstinence-only and 71 chose abstinence-plus; some districts did a combination of the two.

"It's a heavy lift in some communities," said Rachel Canter, executive director of Mississippi First. "There are strong personalities on some school boards who adamantly believe that the Bible says abstinence only."

The debates about which sex education policy to adopt illuminate the values in a state that, according to surveys, is among the most religious in the country.

Sanford Johnson, deputy outreach coordinator for Mississippi First, an education policy group, encountered these values while addressing the school board in Hollandale, a dusty, rural community with a dilapidated downtown of shuttered stores and peeling paint.

Johnson thought he had made a good case for contraception education when he shared disturbing statistics: The local birthrate was 73 out of 1,000 females between 15 and 19; the national rate is 29.4 per 1,000.

He encountered the usual gasps of shock when he revealed that the rate of chlamydia, at 1,346.8 per 100,000 people, was nearly double the rest of Mississippi, and approaching triple the U.S. rate.

But later Johnson got a call from someone who had attended the board meeting — telling him that people who have sex before marriage don't go to heaven. The board voted for abstinence-only.

"This is a very devoutly religious community — church-oriented and Bible-based; that's what they wanted for their children," said Pamela Johnson, the school board president. "The board was adamant that we wanted to implement the curriculum that was based on our community's beliefs."

The school district in Oxford also embraced abstinence-only until Barnard and other mothers complained, speaking out so vocally that some kids in town began calling them the "sex moms."

Dora Chen, a former Oxford High School student now attending Princeton University, was editor of the school newspaper when it ran a story about sex education that featured a pregnant classmate. She endorsed abstinence-plus at the next school board meeting, facing a crowd of people she'd known since childhood.

"The majority of high school students in Mississippi have sex before they graduate," she said in an interview. "To me, if we just do abstinence-only, we're really sort of ignoring the large majority of students in Mississippi."

A month after its initial decision, the board decided to let students learn about contraceptives after all.

Most parents in the state think that some sort of sex-related education should be taught in the schools, according to a study by the Center for Mississippi Health Policy. Teens think so too.

Gabrielle Thomas, 19, was sitting in a McDonald's in Clarksdale on a recent week day, her hands folded over her pregnant belly. Children, some of whom belonged to Thomas' friends, ran shrieking in the play area nearby.

Thomas lives in Coahoma County, which adopted an abstinence-plus sex ed curriculum. Thomas wishes the district had done so sooner. While in school, she learned nothing about how effective condoms are or how much life changes with parenthood, she said.

"They were just saying, 'Don't have sex,'" Thomas said. "They needed to show us more about that."

Even in districts that have adopted abstinence-plus, there are hiccups.

In Oxford, largely because of the difficulties of getting kids to bring back signed parental permission slips, only five students in a seventh-grade class of 30 took sex ed, Barnard said.

Sex ed advocates also have complaints about the law: It requires boys and girls to be taught about sex in separate classes and doesn't allow condom demonstrations in schools. Mississippi First's Sanford Johnson improvised a YouTube demonstration about how to put on a sock after an instructor was chastised for gesturing too much with her hands while talking about proper condom use.

Regardless of what schools teach, there is still a powerful culture in Mississippi that celebrates teen pregnancy, said Ashley McKay, the head of Tunica Teens in Action, a nonprofit group that works with Delta-area teenagers. Teenage girls have photo shoots of their pregnant bodies, and 15- and 16-year-olds have competing baby showers. Until that culture changes, McKay said, lessons about sex in school can't make much of a difference.

McKay, 26, was sitting in a pizza parlor on a recent afternoon with her cousin Caitlin Wicks, 16, and two of her friends. They talked about sex education in Tunica, one of the districts that adopted an abstinence-plus policy.

"He actually showed us pictures, and I was like, 'That's what it looks like? That's disgusting,'" said Wicks, describing photographs shown in class of a gonorrhea infection.

McKay said she never saw such a thing when she was in high school. Teachers barely talked of sex at all.

"They said, 'If you have sex, you will get AIDS,'" McKay said. "'And you're going to die.'"

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